Re: [Qemu-devel] [PATCH] Add support for fd: protocol

[Blue Swirl]

On Fri, May 20, 2011 at 9:48 PM, Corey Bryant <address@hidden> wrote:
> sVirt provides SELinux MAC isolation for Qemu guest processes and their
> corresponding resources (image files). sVirt provides this support
> by labeling guests and resources with security labels that are stored
> in file system extended attributes. Some file systems, such as NFS, do
> not support the extended attribute security namespace, which is needed
> for image file isolation when using the sVirt SELinux security driver
> in libvirt.
>
> The proposed solution entails a combination of Qemu, libvirt, and
> SELinux patches that work together to isolate multiple guests' images
> when they're stored in the same NFS mount. This results in an
> environment where sVirt isolation and NFS image file isolation can both
> be provided.

Very nice. QEMU should use this to support privilege separation. We
already have chroot and runas switches, a new switch should convert
all file references to fd references internally for that process. If
this can be made transparent, this should even be the default way of
operation.